Anchorage and installation tool

ABSTRACT

An anchorage arrangement in the form of a socket (1) and anchor bolts (5) for anchoring scaffolds at walls or the like. The socket (1) has an inner cruciform recess (3) with conical chamfers (4) which are adapted to the form of a conical extension (7) on the anchor bolts (5). When screwing in an anchor bolt (5), the eye (6) of a bolt (5) is placed in the recess (3) of the socket (1), whereby the conical extension (7) of the bolt (5) and the chamfers (4) cooperate, partly to guide the application of the socket (1) onto the bolt (5), and partly to stabilize the bolt (5) in the socket (1) during the operation of screwing the bolt into a wall. The socket (1) is rotated by a drill after inserting an insert pin (2) on the socket in the drill chuck. The conical extension (7) may be an integrated part of the bolt (5), but is preferably threaded on the bolt (5).

FIELD OF THE INVENTION

The present invention relates to an anchorage arrangement for e.g.anchoring of scaffolds at walls or the like, which arrangement consistsof a screw socket and an anchor bolt.

BACKGROUND

When mounting scaffolds the scaffold must be anchored in a safe way.This is done by securing the scaffold at a large number of points byanchor bolts screwed into the wall at which the scaffold is mounted.Today this is normally done by first drilling a hole in the wall, andthen hammering a plug into said hole, whereafter the anchor bolt isscrewed in manually in the the wall in order to anchor the scaffold. Itis both a tiresome and time consuming to manually screw in the anchorbolts.

The concern of the invention is the large strains, specially in theshoulders, experienced by scaffolders in presently used manual method toscrew in anchor bolts. It has been found in practice that theinstallers, due to being pressed for time, often are careless with theimportant anchoring, as it is both time consuming and tiresome to screwin anchor bolts in the prescribed number. Of course this is unacceptablefrom the view point of security.

The use of the anchorage according to the invention is not limited toscaffolds but can be used anywhere when some kind of anchoragearrangement is needed. Examples of other fields of use are railings,fences, wire carriers, fireladders and lifting eye bolts for e.g. rocks.

SUMMARY OF THE INVENTION

Thus, the object of the present invention is to facilitate to screw inthe anchor bolts by making it possible to use an ordinary drillingmachine for the actual screwing in.

This object is met with an anchorage arrangement an anchor boltcooperating with a socket furnished with an insert pin for connectionwith a drilling machine or the like, the socket having a cruciformedinner recess furnished with chamfers formed at each of the inner cornersof the recess and decreasing inwardly in the socket, the chamferscooperating with an extension in the form of a cone on the anchor bolt.

When using the arrangement according to the invention the socket isplaced in a drill chuck, or other suitable rotary drive means, in thenormal way. In the inner cruciformed recess, the eye of the cone on theanchor bolt fits. Furthermore, the anchor bolt has a corresponding formto that of the chamfers on the recess within the socket. The cone andchamfers partly act to guide the application of the socket on the anchorbolt and partly to hinder the stem of the anchor bolt from strikingagainst the parts of the socket during the screwing operation.

In schaffold mounting the normal distance from the plank platform onwhich one stands at the mounting of the anchor bolts and the hole inwhich the anchor bolt is to be screwed in is about 2 m, which gives acumbersome working posture with large strain particularly on theshoulder 3 during the presently used method of manually screwing inanchor bolts. This work is facilitated by the invention by which one canuse the some drilling machine for both screwing in of the anchor boltsand to drill the holes in the wall in which the anchor bolts are screwedin. By using a drilling machine the bolts are screwed in with a greaterforce, which expands the plugs in the wall more and gives a strongeranchoring. Due to the cruciformed recess of the socket with chamferingand the cone of the anchor bolt it is fast and easy to screw in thebolts without the bolt stem striking against the socket. This becomesmore important if the scaffold, as often happens with additionalinsulation, is mounted at a relative large distance from the wallswhereby long anchor bolts must be used. Without the chamfers and thecone it would be very difficult to screw in the anchor bolts withoutthem striking against the socket. Furthermore it is a clear risk thatthe anchor bolts will strike so much that they affect the hole in thewall.

When sheeting the scaffold, i.e. covering it with plastics, almost twiceas many anchor bolts must be used due to the surface exposed to thewind.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is more closely explained below by means of embodimentsshown in the enclosed drawings, in which:

FIG. 1 is a sectional view of the socket taken along the line I--I inFIG. 2;

FIG. 2 is an end view showing the interior of the socket;

FIG. 3 is a side view of one anchor bolt;

FIGS. 4a-4h are side views of different anchor bolts;

FIGS. 5 and 6 are sectional views of the socket furnished with magneticrods and rubber coatings, respectively;

FIG. 7 is a sectional view of the socket furnished with rubber coatingsin accordance with FIG. 6;

FIG. 8 is a sectional view showing a detail of one type of expander; and

FIG. 9 is a plan view of a socket intended for the anchor bolt accordingto FIG. 4e.

The present invention thus refers to a socket and anchor boltarrangement for use in anchoring of scaffolds at walls or the like.

The arrangement consists of a socket 1 with a pin 2 for connection withe.g. a drill chuck and an anchor bolt 5. The interior of the socket 1has a cruciformed recess 3, with chamfers 4. The anchor bolt 5 has aneye 6 and an extension in the form of a cone 7 between the eye 6 and thebolt stem 8. Furthermore the bolt 5 is threaded at 9 so it can bescrewed into the wall.

The cone 7 may be an integrated or welded part of the anchor bolt 5, ora loose cone screwed onto the bolt. The cone 7 may be made of aluminum,steel or the like. The screwable cone is furnished with an interiorthread corresponding to the thread of the bolt 5, the bolt suitablybeing threaded all the way up to the eye 6. By such an arrangement theposition of the cone 7 on the bolt 5 may be altered as required.

When using the invention one may in a normal way drill a number of holesin the wall which then are furnished with plugs. Then the socket isplaced in e.g. a drill chuck (not shown) by means of the inlet pin 2.When the anchor bolts 5 then are to be screwed into the drilled andplugged holes in the building wall the eye 6 of the bolt 5 is placed inthe recess 3, whereby the cone 7 cooperated with the chamfers 4 of therecess 3 in order to give a secure, reliable and stable contact betweenthe anchor bolt 5 and the socket 1.

The screw part 9 of the anchor bolt 5 is adapted to the actual use. Itis thereby possible to use e.g. self-drilling bolts 5 for wood, concreteor lightweight concrete etc., with or without an expander 11. Then thereis no need for any predrilling. Examples of different anchor bolts 5with different kinds of threads 9 are shown in FIGS. 4a to 4h.

The chamfers 4 are largest at the open end of the socket and decreaseinwardly of the socket 1 at the same angle as shown by the cone 7 on theanchor bolt 5. In this way a large contact surface is obtained betweenthe socket 1 and the bolt 5 which functions as a guide for theapplication of the socket on the bolt besides stabilizing the screwing.

Besides acting to guide the socket during the screwing in of the boltthe cone 7 furthermore acts as a stiffening means for the bolt 5 itself.Furthermore, the cone 7 may assist in stiffening of the attachment ofthe anchor bolt in the wall by abutting against the wall.

A further advantage with the anchorage arrangement of the invention isthat for anchor bolts 5 with non-integrated cones 7, the cone may bepost tensioned against the wall in order to further strengthen theanchorage, making the plug in the wall expand better, which gives astronger anchorage. Furthermore it is possible, if necessary, to makethe cone 7 bigger by e.g. design it with a straight part 14a, 14e, 14g,14h after the cone 7. In order to facilitate the post tensioning thecone 7, as well as the chamfers, the straight part may be hexagonal oroctagonal or straight, and may have the form of a nut. The cone is veryimportant at lateral displacement or pressure from above for suspendedscaffolding.

It is suitable to arrange some kind of attachment in the socket 1, i.e.means which keep the bolt 5 in place even if the socket 1 is directeddownwardly. There are many conceivable ways to achieve this. Thepreferred way at present is to, in accordance with FIG. 5, integratemagnetic rods 10 in the socket, which magnets 10 are dimensioned inorder to securely hold the anchor bolts 5 within the socket 1.

Instead of magnets 10 the channels 3 of the socket 1 may be lined withraw rubber 12 in accordance with FIGS. 6 and 7 whereby the frictionbetween the eye 6 and the rubber 11 is enough to keep the bolt 5 inplace. This is particularly suitable when using hammer drills.

In order to be able to replace worn rubber coatings 12 the socket 1 mayconsist of two parts, with the two parts assembled by means of threads(not shown). The joint surfaces of the socket parts can hereby bearranged on any side of the rubber elements 12. When the rubber elements12 are to be replaced the socket is open by unscrewing the two part fromeach other, the worn rubber coatings 12 are taken off and new coatingare put in, whereafter the parts of the socket 1 are once again screwedtogether and then is ready for use.

As a further alternative to the attachment for the bolt 5 in the socket1 it is conceivable to use spring biased clips in the socket 1.

The bolts 5a and 5b according to the FIGS. 4a and 4b, respectively, area self-drilling steel bolt and wood bolt, respectively.

The bolt 5 according to FIG. 4c, which is intended for concrete has aself-drilling end 13c and has an expander 11c. When bolt 5c has beenscrewed in by means of the socket 1 it is post-tensioned by the cone 7cbeing screwed in whereby the expander 11c expands by being pushed ontothe conically expanded part 15c behind the drill end 13c. Such a bolt 5cgives a reliable anchorage and get its strength from several cooperatingfactors such as the pressure of the expander 11c against the walls ofthe drilled hole and the abutment of the cone 7c against the wall inwhich the bolt 5c has been screwed in. It is possible to re-use thisbolt 5c with the expander 11c. When the bolt 5c is to be loosened thecone 7c is first loosened, then the bolt 5c is striked inwardly adistance corresponding to the expansion of the expander 11c, whereby theexpander 11c is compressed by springs arranged in the expander 11c. Inorder to support this movement a pin may be arranged affecting thesprings. The outer surface of the expander 11c may furthermore have theshape of a drill in order to remove material from the drilled hole atthe screwing in. Also, this surface form gives the expander 11c astronger abutment against the drilled hole. The expander 11c can be madeof many different materials such as steel, aluminum, plastics or rubber.If rubber is used it is suitable to arrange small spikes on the outersurface in order to remove material from the drilled hole.

The bolt 5d according to FIG. 4d has a self-drilling end 13d and isintended for lightweight concrete and is furnished with an expander 11d.

The bolt 5e according to FIG. 4e is a wood bolt with open eye 6e. By thespecial form of this eye 6e a special socket 1' must be used, whichcorresponds to the socket 1 above except that instead of the cruciformedinner recess 3 the socket 1' has a recess 3' adapted to the form of theeye 6e. In the example shown the socket 1' is furthermore furnished withmagnetic rods 10.

In FIG. 4f a bolt 5f is shown, has a self-drilling thread 13f and isintended for lightweight concrete.

The bolt 5g according to FIG. 4g has a self-drilling end 13g withexpander 11g intended for concrete. The outer surface of the expander11g has a form which corresponds to a drill in order to remove materialfrom the drilled hole during the screwing in of the bolt.

In FIG. 4h a bolt 5h is shown which has a self-drilling end 13h and adivisible expander 11h with an outer "drill shaped" surface.

A further form of expander 11, which e.g. could be used with the bolt 5haccording to FIG. 4h, is shown in section in FIG. 8. As is evident fromthe figure the inner surface of the expander 11 is furnished with awedge-shaped thread 15 adapted to the thread of the bolt 5. Thisexpander is used as follows. When the bolt 5 has been inserted to thebottom with the cone 7, or its extension 14, abutting against the wallthe cone 7 is held with a wrench, then the bolt 5 is screwed out bymeans of e.g. a screwdriver introduced through the eye 6. Thus expandingthe expander by means of the wedge-shape of the thread 15. The more thebolt is screwed out the more the expander 11 tightens. When the bolt 5then is screwed back in the expander 11 retracts due to the thread 15.This makes it possible to then withdraw the bolt 5.

The different bolts 5a-h in the figures are shown as examples of how theinvention may be used in different ways in practice, and persons skilledin the art realize that there are many different possibilites ofvariation concerning dimension, selection of material, type of threadetc.

What is claimed is:
 1. An anchorage arrangement for anchoring a memberto a wall, said anchorage arrangement comprising a socket and an anchorbolt engageable in said socket, said socket having an inner recessformed by intersecting channels defining a cruciform section for saidrecess, said socket including an extension pin drivingly connectable toa rotary drive means so that the socket can be driven in rotation, saidsocket having four chamfers formed at intersecting corners of thechannels of the recesses, said chamfers extending from an open end ofthe socket inwardly thereof and being tapered to diminish in height asthe chamfers extend inwardly of the socket, said anchor bolt including astem, an end portion on said stem and a conical extension secured tosaid stem, said end portion being engageable in said recess in saidsocket with said conical extension engaging said chamfers.
 2. Ananchorage arrangement as claimed in claim 1, wherein said end portion ofthe anchor bolt comprises an eye, said stem including a threaded endopposite said eye.
 3. An anchorage arrangement as claimed in claim 1,wherein said conical extension is integral with said stem.
 4. Ananchorage arrangement as claimed in claim 1, wherein said stem isthreaded from said end portion to an opposite end of the stem, saidconical extension being threadably engaged on said stem.
 5. An anchoragearrangement as claimed in claim 1, wherein said chamfers are tapered atan angle corresponding to an angle of taper of said conical extension,said conical extension having end diameters which enable the conicalextension to be engageably fitted in said chamfers.
 6. An anchoragearrangement as claimed in claim 1, wherein said bolt includes a selfdrilling end part at an end of the bolt opposite said end portion.
 7. Ananchorage arrangement as claimed in claim 6, comprising an expandermeans in said stem for expanding in a hole in a wall.
 8. An anchoragearrangement as claimed in claim 1, comprising magnetic rods in saidsocket to retain the anchor bolt in said recess in the socket.
 9. Ananchorage arrangement as claimed in claim 1, comprising linings offriction material at said channels of the recess to hold the bolt insaid recess.
 10. An anchorage arrangement as claimed in claim 1, whereinsaid conical extension is made of aluminum, steel or plastic material.11. An anchorage arrangement as claimed in claim 1, comprising anextension portion on said conical extension, said extension portionextending coaxially from said conical extension portion in a directionaway from said end portion.
 12. An anchorage arrangement as claimed inclaim 11, wherein said extension portion on said conical extension isformed as a nut.
 13. An anchorage arrangement as claimed in claim 1,wherein socket is tubular.